1. Field of the Invention
The invention is concerned with an elastic strap fashener assembly, particularly in the form of a respirator harness that employs polymeric components in conjunction with elastic straps.
2. Description of the Related Art
A typical respirator harness is made of polymeric components and elastic straps which are sewn, mechanically secured, or ultrasonically welded to the polymeric components. Doing so requires a first step of molding the polymeric components and then a separate step of attaching each strap to one or more of the polymeric components.
Visual inspection of Respirator Model 1482 of Pro-Tech Respirators, Inc., Buchanan, Mich., indicates that part or all of the harness has been made in a single step. That is, an elastic strap has been laid at the parting line of a 2-part injection mold and so becomes part of the harness when a polymeric component is formed around an end of the strap. Such inspection also indicates that a series of vanes at the face ofa each part of the injection mold abutted each other at the elastic strap when the mold was closed and that the injected composition formed a polymeric cage encompassing an end of the elastic strap. The cage has a peripheral frame interconnected by a central bridgework consisting of longitudinal stringers that were formed in the valleys between the vanes and are fused to opposite faces of the strap. The stringers bridge the transverse members of the frame and keep the elastic strap at approximately the location of a plane bisecting the thickness of the cage.